PRIMARY AMNIOTIC-FLUID CELL, SKIN FIBROBLAST AND LIVER ALPHA-L-FUCOSIDASE AND ITS RELATION TO CYSTIC-FIBROSIS

Cultured skin fibroblast and primary amniotic fluid cell α-l-fucosidase had a double optimum of pH 5.0 and 6.0. α-L-Fucosidase was largely bound as a single peak to DEAE-cellulose at pH 6.6. Sucrose density isoelectric focusing revealed up to seven components with pI values of 4.9, 5.2, 5.4, 5.8, 6.1, 6.5 and 7.1 with their apparent km values (77-500 μmol/l) being higher than that (57 μmol/l) of the unfocused enzyme. Liver, skin fibroblast and amniotic fluid cell α-l-fucosidase was separated into two peaks by gel filtration. Peak one was more active and stable at low pH and more thermostable at 50°C than peak two, while both peaks had an apparent KM of 52 μmol/l. Apart from the different proportions of the peaks separated by gel filtration, the results for the three tissues were similar. The properties of α-l-fucosidase studied were similar for control and cystic fibrosis liver or skin fibroblasts. © 1979.